It's summer time and the Red Sox are playing! Where does one go before or after the game for a good meal? On the other hand, f you are looking to avoid the crowds, don't head to these restaurants if a Sox game is on. Parking will also be hard to find.
Eastern Standard - French bistro food and yummy cocktails! Get the roasted bone marrow. Yum!
Petit Robert Bistro - Similar french bistro spot.
Trattoria Toscana - Small restaurant that serves great Tuscan (Italian) food! They don't take reservations so go there early if you don't want to wait. SO had an extremely unpleasant experience with the service here, so just a warning :P